Scissor sharpener



Sept. 15, 1970 J MccUE 3,528,204

SCISSOR SHARPENER Filed Jan. 31, 1968 III/(III,

s k/ lMS M605 INVENTOR.

W w Nam- United States Patent 3,528,204 SCISSOR SHARPENER James H. McCue, 2200 Arroyo Blvd., Altadena, Calif. 91002 Filed Jan. 31, 1968, Ser. No. 702,063

Int. Cl. B24b 23/00 U.S. Cl. 51--173 7 Claims ABSTRACT OF THE DISCLOSURE A scissor sharpener comprising a base on which a pair of freely rotatable grinding wheels are mounted side by side for rotation about parallel axes with the blade contacting side faces thereof located in a common plane. The grinding wheels each carry a resilient rubber disc of lesser diameter than the wheel disposed at the grinding face side thereof for contact by the side of the blade being ground. Frictional engagement of the peripheries of these discs by the side of the blade being ground incident to relative movement longitudinally of the blade provides rotative power to the grinding wheels as the blade moves across the face thereof in a line tangent to the peripheries of the rubber disc.

BACKGROUND OF THE INVENTION Field of the invention The field of the invention is that of sharpening devices for scissors, shears and comparable cutting instrumentalities.

Prior art Many attempts have been made to provide a scissor blade sharpening device which was both economical to manufacture, compact in form, and capable of use without the need of special skills. For the most part, such devices have contemplated movement of the blade longitudinally over a stationary surface which resulted in the grinding being done by abrasion parallel to the length of a blade. Alternatively, the abrading element was moved longitudinally of the blade. Those grinders and sharpening devices for scissors and the like which employed a rotating abrading member have required an external power source.

SUMMARY OF THE INVENTION The present invention has for its principal objective the provision of a sharpener for scissors and comparable instrumentalities, e.g., tin snips, hedge shears, etc. in which (a) the abrading means has a path of travel which is transverse of the length of the blade edge and (b) in which the contact with the blade being ground and relative movement between the device and the blade provides the power for rotating the abrading means and consequent abrading movement transversely of the length of the blade edge.

Another objective of the invention is to provide a sharpening device of the foregoing character which is compact in form, simple in construction and economical to manufacture.

A further objective of the invention is to provide a sharpener of the above character which may be held in the hand of the user and applied to the blade being sharpened.

Still another objective of the invention is to provide a device of the above character which may be mounted on a suitable bench or other support to permit the blade to be ground to be brought into contact therewith and move back and forth thereon.

With the foregoing objects in view, together with such other objects and advantages as may subsequently appear,

3,528,204. Patented Sept. 15 1970 the invention resides in the parts, and in the construction, combination and arrangement of parts described, by way of example, in the following detailed description of certain presently preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings which form a part of the specification following and which illustrate certain presently preferred embodiments of the invention:

FIG. 1 is a perspective View of a first presently preferred embodiment of the invention shown in the position of use as employed to sharpen a scissor blade;

FIGS. 2 and 3 are, respectively, top and bottom plan views, having references to the position of use shown in FIG. 1, of the first embodiment of the invention, a portion of the frame structure of FIG. 3 being broken away to show details of interior construction;

FIG. 4 is an enlarged scale, sectional view taken on the staggered line 4-4 of FIG. 2;

FIG. 5 is an exploded perspective view of one of the grinding wheel assemblies;

FIG. 6 is a perspective view of a second presently preferred embodiment of the invention particularly useful for larger types of scissor-like implements; and,

FIG. 7 is a fragmentary sectional view taken on the line 7-7 of FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawing and particularly to FIGS. 1-5 thereof, the first illustrated embodiments comprises a hollow, relatively thin, generally rectangular case open along one edge face thereof and comprising a frame member 1 including in integral formation a side which, with reference to the usual position of use of the device, will be designated as the top 2 and a bounding side wall 3. As viewed in plan, three of the corners may be of relatively large curvature as indicated at 4 while the left hand forward corner 5 is of much lesser curvature for a purpose presently to be referred to. The lower edge of the side wall 3 is provided with a shallow longitudinal groove 6 in which a complementary rib 6' of the bottom member 7 is received, said bottom member, as viewed in plan being generally of the same contour as the top surface of the frame member.

For convenience, the open side of the case will be referred to as the front side of the device and the diametrically opposite portion of the side or edge wall will be referred to as the rear side of the device. The top 2 is provided adjacent the front edge thereof with a pair of depending cylindrical posts 8, -8 adjacent the opposite corners of said front edge, said posts extending to the plane of the inner face of the bottom member 7, and screws 9, 9 extending through the bottom member threadedly engage complementary threaded bores in the ends of the post to serve in part to secure the bottom to the frame member. Additionally, the top 2 carries depending posts 10, 10 adjacent the rear corners thereof and screws 11, 11 extend through the bottom and threadedly engage the posts 10, 10 thus cooperating with the posts 8, 8 and screws 9, 9 to secure the bottom to the frame member 1.

In addition to serving as securing means for the case, the posts 8, 8 serve as bearings for identical grinding assemblies 12, 12 which are freely rotatable thereon. Since the assemblies are identical, a description of one will serve for both. Rotatably mounted on the post 8 is a sleeve member 13 of such length as to have a minimum of end play between the opposed surfaces of the top and bottom of the case. At its upper end, the sleeve carries a flange member 14 formed integrally therewith, said flange having a diameter such that a portion thereof projects beyond the front edge of the top 2. Preferably, the portion of the flange visible beyond the front edge of the top is perforated as at or is otherwise given some configuration so that rotative movement thereof may be immediately noted.

The exterior surface 16 of the sleeve 13 is of non-circular configuration in transverse cross-section here shown as hexagonal but any non-circular configuration would serve as well as will be presently appreciated. Mounted on the exterior of the sleeve 13 and juxtaposed with the flange 14 is the grinding wheel 17 formed of a suitable abrasive material, the wheel having a center opening 17 closely and non-rotatively fitting the exterior surface 16 of the sleeve and preferably having an outer diameter somewhat greater than that of the flange 14. The lower face 18 of the grinding wheel lies in a plane normal to the axis of rotation of the sleeve 13. Mounted on the sleeve 13 and non-rotatively engaging the outer surface 15 thereof below the wheel 17 and substatntially filling the space between the lower face 18 of the grinding wheel and the inner face of the bottom member 7 is the driving pulley 19 of which at least the outer peripheral surface 20 is formed of a slightly resilient rubber or rubberlike material and being of a diameter such as to project only slightly beyond a vertical plane containing the edge of the bottom member 7 bordering the open front edge of the case.

From the foregoing description, it will be seen that each of the posts 8, 8 serve as bearings for the identical wheel assemblies each comprising a combined sleeve and flange, a grinding wheel, and a driving pulley and that each assembly is free to rotate thereon as a unit, the posts additionally serving as a portion of the securing means by which the bottom member is secured to the frame member whereby the screws associated with these posts serve both to secure the frame structure together and to secure the assembly in position in the device.

Referring now to FIG. 1 a typical mode of use of the device is illustrated. A pair of scissors S is opened to the widest extent and is held in the left hand with the blade B having its inner face toward the user positioned with the cutting edge thereof in a substantially horizontal attitude. The device is applied to that blade (see FIG. 4) with the lower surfaces of both of the grinding wheels resting on the cutting edge and with the peripheral edges of the associated driving pulleys contacting the inner face of the blade. Then tilting the device so that the lower faces 18 of the wheels are approximately parallel to the plane of the surface of the top edge of the blade, and pressing both downwardly and toward the blade, the device is moved back and forth along the blade. The frictional engagement of the driving pulleys with the side of the blade will cause the grinding wheels to rotate as they move along the blade thus producing a grinding action that is not transverse to the length of the blade but, due to the rotation of the grinding wheels is in intersecting, generally diagonal directions transversely of the blade. This produces a quick and positive grinding action resulting in a sharp edge with only a few strokes of the device along the blade. After the first blade is ground, the scissors is turned and the other blade is similarly sharpened. The front top corner 5 of the frame member by contacting the blade not being ground when the device is moved to the inner end of the blade, serves to prevent contact of the other blade by the periphery of the adjacent grinding wheel.

Referring finally to FIGS. 6 and 7 there is shown a modification of the invention better suited for use with heavier shears such as those used in tailoring establishments or in other activities using shears which are of such size and Weight as not conveniently to be sharpened by the first embodiment of the invention. In this form of the invention, one of the case components 21., here shown as the equivalent of the frame member 1, is provided with an integrally formed flange or foot portion 22 extending at right angles thereto whereby the case and a single driving wheel assembly 12 mounted therein may be fixedly mounted on a bench or other supporting surface in a vertical attitude so that the scissors blade to be sharpened may be held by both hands of the user and be guided back and forth while being pressed inwardly against the grinding wheel surface and downwardly against the associated driving pulley. The omitted grinding wheel assembly is replaced by an upwardly projecting tongue portion 23 formed on the member '21 presenting a vertical surface 24 in the plane of the grinding wheel face 18 and a second upwardly projecting tongue 25 on the case cover portion 26 presenting an end face portion 27 in the horizontal plane of the periphery of the driving pulley 19. It will be understood that, if desired, either of the two embodiments may be provided with single or plural grinding wheel assemblies and that the fact that each embodiment is shown with a particular arrangement does not signify that that embodiment is thus limited.

Thus there has been provided a rotating grinding wheel type of scissor sharpener in which the movement of the scissor blade across the grinding wheel surface provides the power for imparting the desired rotation to the grinding wheel with the result that the grinding action is at least substantially transversely of the length of the blade being ground and in which the means which unites the member forming the case serve also as the supporting means for the grinding assemblies of the device. While the latter feature is, of course, desirable for economy of manufacture. For industrial uses of the invention such as shown generally in FIGS. 6 and 7 it is appreciated that types of construction other than that illustrated may be employed, for instance, the bottom member of the illustrated case might either be dispensed with or be formed to constitute the means by which the grinding means comprising either one or two assemblies might be mounted on a supporting surface. Other variations and modifications have also been suggested in the detailed description of the invention. In view of these considerations, it is believed to be evident that the invention is not necessarily deemed to be limited to the precise details of construction thus disclosed by way of example of certain presently preferred embodiments and it will be understood that the invention includes as well all such changes and modifications in the parts, in the construction, combination and arrangement of parts as shall come within the purview of the appended claims.

I claim:

1. In a sharpening means for the blades of scissors and the like, a supporting base, a pair of grinding wheels, each mounted for free rotation about parallel axes on said base and each having at least a portion of a side face thereof exposed for simultaneous contact by the cutting edge of a scissor blade to be sharpened, and a driving means for each grinding wheel for effecting a positive independent rotation of each grinding wheel, each comprising a member of lesser diameter than said grinding wheel mounted for rotative movement with said grinding wheel about the axis of rotation thereof and including a peripheral surface possessing a high coefficient of friction disposed adjacent to and extending normal to said blade edge contacting face of said grinding wheel, said surface of said rotation effecting member being effective, in response to longitudinal movement of a scissor blade adjacent to the edge to be ground While subjected to pressure against said peripheral surface of said member, to convert the longitudinal movement of the blade into rotation of said grinding wheel, and where the blade contacting faces of said grinding wheels are in the same plane and the peripheral surfaces of said pair of driving means define a straight line path of movement of a scissor blade across said blade contacting faces of said pair of grinding wheels.

2. A scissor blade sharpening means as claimed in claim 1 in which said base is hollow and open at one edge face thereof and comprises frame and cover components, and in which axle means for said grinding wheels serve in part as means for interconnecting said components.

3. A scissor blade sharpening means as claimed in claim 1 in which said base includes means for mounting said base on a supporting surface.

4. A scissor blade sharpening means as claimed in claim 1 in which said base comprises a frame component and a cover component detachably connected thereto, and in which the interconnection of said frame and cover components serves, additionally, to secure said grinding wheels and said driving means assembled together for free rotation on said base.

5. A scissor blade sharpening means as claimed in claim 1 in which each of said grinding wheels and its said driving means are interconnected by non-circular, complementary engaging surfaces effective to prevent relative rotation thereof.

6. A scissor blade sharpening means as claimed in claim 1 containing observation means for providing a visual means indicative of the rotation of said grinding wheels, connected to said grinding wheels so that rotation of said wheels may be observed.

7. A scissor blade sharpening means as claimed in claim 6 wherein said observation means comprises a pair of plates, each plate rotatably mounted to one of said grinding Wheels and containing visible indicia which provides a visual indication of rotation of said grinding Wheel.

HAROLD D. WHITEHEAD, Primary Examiner US. Cl. X.R. 51-210; 76-822 

